fixed heratic parsing error, minor changes

@@ -69,7 +69,7 @@ tokens = (
     'DOUBLE_MINUS',
     'PLUS',
     'MINUS',
-    'TIMES',
+#    'TIMES',
     'DIV',
     'MODULO',
     'DOUBLE_AMPERSAND',
@@ -169,7 +169,7 @@ t_DOUBLE_PLUS = r'\+\+'
 t_DOUBLE_MINUS = r'--'
 t_PLUS = r'\+'
 t_MINUS = r'-'
-t_TIMES = r'\*'
+# t_TIMES = r'\*'
 t_DIV = r'/(?!\*)'
 t_MODULO = r'%'
 t_DOUBLE_AMPERSAND = r'&&'

@@ -755,9 +755,7 @@ def p_empty(t):
     pass
 
 def p_error(t):
-    print("You've got a syntax error somewhere in your code.")
-    print("It could be around line %d." % t.lineno)
-    print("Good luck finding it.")
+    print("[%s:%s] syntax error" % (t.lineno, t.lexpos))
     raise ParseError()
 
 yacc.yacc(debug=1)

@@ -2,6 +2,15 @@ import argparse, sys, os.path
 
 import ply.yacc as yacc
 from . import cparse, cvisitors, cx86
+cttc = cx86
+
+ARCH = {"x86" : cx86,
+        "ttc" : cttc}
+
+ARCHDOC = """supported target architectures:
+  x86    Intel 80x86 assembly (in GNU Assemble format)
+  ttc    The Tiny Computer assembly
+"""
 
 class CompileError (Exception) :
     "Exception raised when there's been a compilation error."
@@ -11,7 +20,8 @@ class Compiler (object) :
     """This object encapsulates the front-end for the compiler and
     serves as a facade interface to the 'meat' of the compiler
     underneath."""
-    def __init__ (self) :
+    def __init__ (self, arch) :
+        self.arch = arch
         self.total_errors = 0
         self.total_warnings = 0
     def _parse (self) :
@@ -31,12 +41,15 @@ class Compiler (object) :
         self._compile_phase(cvisitors.SymtabVisitor())
         self._compile_phase(cvisitors.TypeCheckVisitor())
         self._compile_phase(cvisitors.FlowControlVisitor())
-        self._compile_phase(cx86.CodeGenVisitor(outfile))
+        self._compile_phase(self.arch.CodeGenVisitor(outfile))
         if ast_file is not None:
             self._compile_phase(cvisitors.ASTPrinterVisitor(ast_file))
     def _print_stats (self) :
         "Prints the total number of errors/warnings from compilation."
-        print("%d errors, %d warnings." % (self.total_errors, self.total_warnings))
+        if self.total_errors :
+            print("%d errors" % self.total_errors)
+        if self.total_warnings :
+            print("%s warnings" % self.total_warnings)
     def compile (self, code, outfile, show_ast) :
         "Compiles the given code string to the given file object."
         self.code = code
@@ -54,21 +67,32 @@ class Compiler (object) :
         return 0
 
 def main (args=None) :
-    parser = argparse.ArgumentParser(prog="cct")
+    parser = argparse.ArgumentParser(prog="cct",
+                                     epilog=ARCHDOC,
+                                     formatter_class=argparse.RawDescriptionHelpFormatter)
     parser.add_argument("-o", action="store", metavar="PATH",
                         type=argparse.FileType('w'), default=sys.stdout,
                         help="write output to PATH")
     parser.add_argument("--ast", action="store_true", default=False,
                         help="dump AST for each C file")
+    parser.add_argument("--arch", action="store", choices=list(ARCH),
+                        default="ttc",
+                        help="output assembly for specified architecture (default 'ttc')")
+    parser.add_argument("-t", "--ttc", action="store_const", const="ttc",
+                        dest="arch", help="output TTC assembly")
     parser.add_argument("source", nargs="+", metavar="PATH",
                         help="C source files(s) to compile")
     args = parser.parse_args(args)
     for src in args.source :
+        print("Compiling %r" % src)
         if args.ast :
-            ast_file = open(os.path.splitext(src)[0] + ".ast", "w")
+            ast_path = os.path.splitext(src)[0] + ".ast"
+            print("Dumping AST to %r" % ast_path)
+            ast_file = open(ast_path, "w")
         else :
             ast_file = None
-        retval = Compiler().compile(open(src).read(), args.o, ast_file)
+        code = "\n".join(open(src).readlines())
+        retval = Compiler(ARCH[args.arch]).compile(code, args.o, ast_file)
         if ast_file is not None :
             ast_file.close()
         if retval != 0 :